An internal combustion engine may be operated in a variety of ambient conditions and under varying loads. For example, an engine may be operated as part of a system for generating electric power, such as, for example, as part of a generator set. A generator set may be operated in high or low ambient temperatures and may be subjected to high or low power loads. As a result, it may be desirable for a system for controlling temperature of the engine to have a flexible capacity for cooling and/or heating the engine.
For example, in order to operate in high ambient temperatures and/or under high power loads, a system for controlling engine temperature may need to be designed to provide high cooling capabilities to meet cooling demands associated with high temperatures and/or high power loads. Such a system may necessitate selection of a high capacity (coolant) pump. One possible drawback of selecting a high capacity pump, however, is that such a pump may result in inefficiencies due, for example, to parasitic losses associated with a high capacity pump, if the ambient temperature and/or power load do not require operation of a high capacity pump. In addition, if the ambient temperature is low and the engine is part of, for example, a generator set that has not been operating, it may be difficult and/or inefficient to start the engine if the engine is relatively cold. Thus, it may be desirable to provide a system for controlling temperature of an engine that operates more efficiently across varying ambient conditions and/or power loads to cool and/or heat the engine.
To reduce the parasitic losses created by a high capacity pump, efforts have been made to include a second pump that assists the first pump in cooling an engine. For example, U.S. Pat. No. 6,082,626 issued to Morikawa et al. on Jul. 4, 2000 (“the '626 patent”), discloses a cooling water system that includes a mechanically-driven first water pump and an electrically-driven second water pump, where both water pumps circulate cooling water through an engine system. The second water pump in the '626 patent helps to circulate an additional amount of cooling water through the system during the engine's operation. Although the second water pump disclosed in the '626 patent may provide additional cooling water through the engine system, the second water pump is only used for cooling the engine system.
The apparatuses of the present disclosure may be directed toward improvements in the existing technology.